This is possibly not true. How many people out there think Space Wolves will retain Runic Weapons that nullify psy powers (vs. just buff their own unit's Deny the Witch)?
Nobody?
OK, so maybe it is true.
The state of the 40k Meta is not bad right now, save 2 builds that make the game incredibly difficult to prepare for.
These are:
Jetstar
Screamerstar
Long story short, these lists rely on extremely powerful units that are geared/equipped/ruled to be able to kill technically anything in cc, yet are also extraordinarily fast, separable, and possessed of some form of re-rollable 2+ saves. By far the NASTIEST of these is the Jetstar.
Jetstar lists can be run a variety of ways. In my opinion, the strongest at present was run by Matt DeFranza at the Battle for Salvation.
In general, these lists revolve around 5-6 squads of Guardian Jetbikes, a squad of Dark Eldar Warriors [to enable ...] Baron Sathonyx, 2 Wraithknights (or a set of Wave Serpents if you prefer, which I personally do not if you're doing it "right"), a pair of Farseers on Jetbikes (both with Runes of Warding/Witnessing to prevent Fortune Fails and Misfortune/Terrify/Hallucinate; one with the Shard of Anaris for Fearless), several squads of Swooping Hawks and 10 Warlocks on Jetbikes, with a few spears optionally to fill in points.
This list is custom built to 6th Edition, combining psychic powers and special rules for the ability to win almost any objective-based mission (which should be 5 of 6 Tournament Missions if you're reflecting the game's design), and to field a unit with extreme mobility and a re-rollable 2+ armor save, cover save, and re-rollable 4+ Invul Save (with optional 2+ re-rollable invul save if you want / position for it). The unit also has Hit and Run and Fearless, and it fails its Hit and Run on only a 6. It has extreme mobility (able to move 48" a turn if needed ... trailing behind to keep Baron in coherency for shorter moves ... and able to split into 4 distinct units, 3 of which can go anywhere, AFTER buffing everyone with powers like Fortune and Protect, so the splitting units are all 2+ re-rollable cover/armor when they split).
Hopefully we can all figure out you can't torrent these units down. Many armies in the current meta CAN torrent down a 3+ re-rollable save. No armies can torrent down a 2+ re-rollable (barring dumb luck).
Moreover, these armies are backed by bunches of Guardian Jetbike units that score and contest effectively, and also can move 48" at any point. Coupled w/ the ability to often enough get Scrier's Gaze and keep them off the table until Turn 4, it can be hard to actually draw a bead on them (much less do so without getting pinned down or outright destroyed by the highly mobile council in your face, or the 2 Wraithknights that in the idea situation should be trailing it).
The catch here is that even now, a properly designed Tyranid list trumps BOTH these armies rather dramatically, due to the mobility and model count of units like Gargoyles, coupled w/ Shadow in the Warp on a hide-able model like the Parasite of Mortrex. Being able to jam a 12" aura of "take your key LD tests on a 3d6" down the throat of an army built around a relative paucity of firepower and the presence of a big honking 2+ re-roll unit dependent on psychic powers to function is a pretty effective way to take them down.
Moreover, Tyranid lists have the bodycount in throwaway or "it's ok if they aren't doing anything" troop units like Termagants to properly bubble wrap objectives against late game contests / controls from units like the council and guardian jetbikes. They also possess key abilities like mass poison, to make the prospect of Wraithknights getting tangled into big 30-model gargoyle and/or termagant squads not all that terrifying (in fact, Parasite outright loves a chance to fling rending instant-killing attacks at Wraithknights).
That all said, Tyranid are neither overly popular nor overly present in contemporary 40k, and the "right" list with the current Codex takes far too long to play (making it painful physically in a tournament setting, and also downright unsporting for your opponent).
We're also about to get a new Tyranid codex.
So what should we all be hoping?
a) The new Tyranid have optimal lists that can be played reasonably in a tournament setting without utterly destroying either your back or your opponents' patience.
b) The new Tyranid are good enough to be taken by a fairly large # of players, thus forcing Jet/Screamerstar players to face the concept they are fairly likely to run into them during a typical GT.
AND BY FAR MOST IMPORTANTLY:
c) The new Tyranid retain Shadows in the Warp or see it buffed, in its ability to apply psy power dampening or nullifying auras to portions of the table. If Shadows in the Warp sees a nerf the likes of which Runes of Warding suffered, and simply applies something like Adamantium Will to units in range, the game of 40k will in my opinion be broken, and will require a basic rule tweak added to the tournament environment akin to:
"Any re-rolled save only succeeds on a 4+."
/$.02
PS - Jetstars can be played around, can be meta'ed for (at risk to getting pantsed by everything else), can be beaten. In the hands of decent players, however, and as the proper jet council "net list" becomes more and more well known and played (it's also SUPER AFFORDABLE TO BUILD FINANCIALLY), it's going to become a serious problem at the average tournament, for the average player. TOs always have these folks in mind first and foremost. We care LESS about the person who is a 40k Savant and thinks he can handle any combo any time. I'm sure you can. You're not the majority of people attending events and having to deal with things like a unit that can contest the entire board at any time, and passes 35/36 saves.
